Zolpidem (Ambien®) versus Temazepam (Restoril®)
Based on "Sleep Disorders Medicine"
written by Dr. Sudhansu Chokroverty, MD
Difference between Zolpidem and Temazepam
Zolpidem, a short half-life non-benzodiazepine, versus temazepam, a medium half-life benzodiazepine, comparison chart:
Zolpidem |
Temazepam | |
| Brand name/Year of initial approval | Ambien®, 1992 | Restoril®, 1981 |
| Formulations | Oral tablets, sublingual tablets, oral spray | Oral capsules |
| Legal status | Schedule IV Controlled substance |
|
| Drug class | Bon-benzodiazepine sedative-hypnotic, short-acting | Benzodiazepine receptor agonist, intermediate acting |
| FDA-approved Indications | • Short-term treatment of insomnia, generally for sleep-onset insomnia | • Short-term treatment of insomnia (generally 7 to 10 days). |
| Mechanism of action | • Zolpidem facilitates GABAergic neurotransmission through a positive allosteric modulation of GABA (A) receptors. | • Non-selective modulation of GABA to increase GABA affinity for GABA receptor |
| Half-life | 2.5-3 hours | 8.8 hours (range from 3.5 to 18.4) |
| Oral bioavailability | ~70% | 96% |
| Metabolism, Elimination | Hepatic metabolism, converted to inactive metabolites, which are excreted by the kidneys. Elimination of the drug is slower in patients with chronic renal insufficiency. |
No hepatic metabolism. Metabolized via conjugation. 80-90% of unchanged drug is excreted in the urine, 10% in the feces. |
| Contraindications | • Hypersensitivity | • Pregnancy • Hypersensitivity |
| Warnings & precautions | • Severe anaphylactic reactions | • Severe anaphylactic reactions • Use with caution in severely depressed patients or those with sings of latent depression |
| Abnormal behaviors | May cause complex sleep-related behaviors such as sleep-eating or sleep-driving with no memory of the event. | |
| Side effects | • Dizziness, drowsiness, confusion, headache, nausea, diarrhea, hallucinations, sleepwalking, amnesia. | • Hemodynamic side effects, orthostatic hypotension3 • Drowsiness, fatigue dizziness, daytime impairment, hangover |
| Rebound insomnia | Zolpidem has no advantages over temazepam with respect to rebound insomnia2. | |
| Driving ability after-midnight intake | Both zolpidem and temazepam do not produce significant residual side effects on psychomotor performance 4. | |
| Effects on physical performance capacity | Single dose of either hypnotic does not negatively affect physical performance characteristics6. | |
| Abuse, physical dependence, tolerance | Zolpidem has lower risk for abuse, withdrawal, and tolerance compared to non-selective benzodiazepines | |
| Drug interactions | Increased sedation and depressive effects when taken with other CNS depressants. | |
| Food interactions | No | |
| Pregnancy category | C | X Can cause teratogenic effects on fetuses |
| Onset of sedative effect | Rapid onset | Delayed onset |
| Time to maximal drug effect 1 | 0.5-1.0 hours | 2-3 hours |
| Advantages | • Preferred hypnotic for people with problems falling asleep • Sublingual zolpidem is a good choice for middle of the night wakening • Less hangover effect • Lower risk of tolerance and withdrawal |
• Temazepam may be useful for concomitant anxiety. • May be preferred hypnotic for insomniacs with liver disease. • Due to longer half-life temazepam may be a better choice than zolpidem for insomniacs who awaken frequently (sleep maintenance insomnia) |
| Disadvantages | • More likely to cause hangover • Slow gastrointestinal absorption compared to other sedative • Temazepam has a slow onset of action and is not a ideal choice for sleep-onset insomnia |
|
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Zolpidem is an imidazopyridine hypnotic that is biochemically distinct from classic benzodiazepines in that it may be selective for the BZ1 receptor subtype and shows a different pattern of distribution of binding sites1. Zolpidem lacks anxiolytic, muscle relaxant and anticonvulsant actions.
Transient insomnia
| Results of double-blind study of efficacy of zolpidem versus temazepam in transient insomnia 5 | Zolpidem | Temazepam |
| Dose regimen | 10 mg 15 min before lights out | 15 mg 15 min before lights out |
| Hypnotic effects | Reduced awakenings and wake after sleep onset | |
| Improved sleep efficiency and subjective sleep measures | ||
| Symbol copying test, morning sleepiness, morning concentration | Not affected | |
| Digit symbol substitution test | Significantly reduced morning test performance | |
Further reading
References
- 1. Rush CR, Griffiths RR. Zolpidem, triazolam, and temazepam: behavioral and subject-rated effects in normal volunteers. J Clin Psychopharmacol. 1996 Apr;16(2):146-57. PubMed
- 2. Voshaar RC1, van Balkom AJ, Zitman FG. Zolpidem is not superior to temazepam with respect to rebound insomnia: a controlled study. Eur Neuropsychopharmacol. 2004 Aug;14(4):301-6. PubMed
- 3. Shi SJ, Garcia KM, Meck JV. Temazepam, but not zolpidem, causes orthostatic hypotension in astronauts after spaceflight. J Cardiovasc Pharmacol. 2003 Jan;41(1):31-9. PubMed
- 4. Partinen M1, Hirvonen K, Hublin C, Halavaara M, Hiltunen H. Effects of after-midnight intake of zolpidem and temazepam on driving ability in women with non-organic insomnia. Sleep Med. 2003 Nov;4(6):553-61. PubMed
- 5. Erman MK, Erwin CW, Gengo FM, et al. Comparative efficacy of zolpidem and temazepam in transient insomnia. Hum Psychopharmacol. 2001 Mar;16(2):169-176. PubMed
- 6. Gremion G, Sutter-Weyrich C, Rostan A, Forster A. Physical performance and sedation: comparative study of the effects of a benzodiazepine (temazepam) and of a non-benzodiazepine hypnotic (zolpidem). Schweiz Z Sportmed. 1992 Sep;40(3):113-8. PubMed
Published: November 24, 2016
Last updated: November 28, 2016
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